This invention relates generally to the field of medical imaging, and more particularly to a method and system for associating exposed radiographic films with proper patient information.
Many modern hospitals have implemented a variety of digital medical modalities such as a magnetic resonance (MR), computed tomography (CT), digital radiography, and ultrasound devices. These modalities, often referred to as input imaging devices, produce vast numbers of diagnostic quality digital images. In order to handle the large volume of digital images, many hospitals have implemented networks of specialized equipment and components specifically designed to facilitate medical radiological imaging. Such a network is commonly referred to as a Picture Archiving and Communicating System (PACS). A PACS allows a radiologist to easily manage digital medical images including storing, retrieving, and viewing the images. For example, when a patient is imaged by a medical modality, a series of digital images, often referred to as a xe2x80x9cstudyxe2x80x9d, is generated and archived at a central database. Typically each study contains general patient information such as name, date of birth, an assigned physician and the type of medical modality that produced the images. This information is often entered by hospital personnel from a workstation while the patient is being imaged. After imaging is complete, a radiologist can easily retrieve the patient""s study from the database and print the images on a medical imager.
A medical imager processes the pixel data of the retrieved medical images and generates output image data. For example, in a continuous tone laser imager, the output image data represents exposure levels necessary for a scanning assembly to accurately reproduce the original image on an imaging element. The output image data is used to modulate the intensity of the scanning laser while exposing the imaging media, thereby forming the visible representation of the original image. Other medical imagers use different imaging techniques to form output images such as direct thermal imaging, ablation imaging, dye transfer, ink jet, dye sublimation and thermal mass transfer.
In addition to easily printing stored medical images, a PACS allows a radiologist to view each image on a diagnostic-quality display station. This eliminates any expense and effort involved in printing the images. Furthermore, after viewing the images, the radiologists can forward the study to another radiologist, perhaps located at a remote hospital, for further review. In this fashion, PACS have greatly improved patient care and the efficiency of radiology departments.
One area that has not benefited from the recent progress in managing and archiving images is conventional radiography (X-ray). In conventional radiography, a radiographic film captures an image-wise exposure of a patient. The exposed film is then chemically developed to form a visible image. Because of the high image quality, conventional radiography is still the predominant diagnostic technique employed by radiologists. Unfortunately, because of the exposure and development process, conventional radiography has been unable to enjoy the benefits associated with digital imaging described above. Many hospitals have attempted to address this problem by turning to film digitizers which digitize radiographic images formed on radiographic films. Once the radiographic image is available in digitized form, such an image can be archived, retrieved and manipulated in any of the various ways offered by a PACS. For this purpose, the developed film is manually removed from the developer and fed into the film digitizer. This approach, although producing a digital image, requires vast amounts of time and labor. Furthermore, manual operations are required in order to associate each digitized image to the proper patient and the communication of the complete study to the PACS. Such a manual operation requires a high degree of attention and is prone to error. For example, patient information is often associated with the wrong image. Another attempt to solve the above problem, as discussed in U.S. Pat. Nos. 5,237,358, 5,583,663 and EP 452,570, has been to directly couple the film processor to the film digitizer such that developed film is fed directly into the film digitizer. This technique requires less time and manual labor and offers other benefits including reducing the chance the film is blemished with finger marks, dust, or the like. This technique, however, does not address the problem that the generated images must be associated with the proper patient information.
By facilitating the management of digital medical images, PACS have greatly improved patient care and the efficiency of radiology departments. For the reasons stated above, and for other reasons stated below which will become apparent to those skilled in the art upon reading and understanding the present specification, there is a need in the art for a method and system which facilitate the use of conventional radiographic film in a PACS environment. There is also a need for a method and system which automatically associates medical images from exposed radiographic film to correct patient information.
The present invention is directed to a method and system for automatically associating a radiographic film with one of a plurality of patients. In one embodiment, the present invention generates a unique code for each patient that is scheduled for examination. When a particular patient is to be examined, the patient""s corresponding unique code is imaged on an unexposed radiographic film. The patient""s image is captured on the radiographic film which is then developed to form at least one visible medical image on the radiographic film. The developed radiographic film is digitized to produce digital image data. According to the present invention, the digital image data is analyzed to determine the unique code of the examined patient that was imaged on the film. The proper patient information is associated with the developed radiographic film based on the unique code as determined from the digital data. According to one aspect of the present invention, the digital image data is analyzed according to optical character recognition techniques.
According to yet another aspect, the present invention stores patient information in an information table having a plurality of entries such that each entry of the information table can be accessed by one the unique identifiers. After a radiographic film is digitized, the information table is accessed according to the unique identifier determined from the digital image data in order to retrieve proper patient information. In one embodiment, the present invention retrieves current patient information from a radiology information system.
According to one feature, the present invention retrieves the proper patient information and communicates the digital image data and the retrieved patient information to a Picture Archiving and Communicating System. In one embodiment, the digital image data and the retrieved patient information is communicated in compliance with the DICOM standard, such as by constructing a DICOM file.
According to yet another aspect, the present invention provides a visual display to allow an operator to modify the patient information of the information table. For example, an error message is displayed when the present invention is unable to determine the unique patient identifier from the digital image data. Providing a visual display allows the operator to enter patient information for the developed radiographic film.
In another embodiment, the present invention is a system for associating a radiographic film with one of a plurality of patients. The system includes an imager for imaging a label having a unique patient identifier on radiographic film. The system further includes an input imaging device having a processor for developing the radiographic film with the label imaged thereon, thereby forming at least one visible medical image on the radiographic film. A film digitizer is coupled to the processor for digitizing the medical image and the label image, thereby producing digital image data. An interface device receives the digital image data and analyzes the digital image data in order to correctly associate the developed radiographic film with one of the patients. According to one aspect of this embodiment, the interface device stores patient information in an information table having a plurality of entries such that each entry of the information table has a unique identifier. The interface device selects one of the entries of information table when the entry""s unique identifier corresponds to the unique patient identifier of the label as determined from the digital image data.
According to one aspect of this embodiment, the interface device further comprises (i) a patient identification station for managing the information table including retrieving patient information from the selected entry, and (ii) a network interface for receiving the digital image data from the input imaging device and communicating the patient identifier to the patient identification station. According to another aspect of this embodiment, the network interface includes a DICOM manager for building a DICOM file containing the digital image data and the patient information received from the patient identification system, wherein the network interface communicates the DICOM file to a Picture Archiving and Communicating System. These and other features and advantages of the invention will become apparent from the following description of the preferred embodiments of the invention.